


Under The Sea

by abiotic_butterfly



Series: My Attempts At Intercourse [3]
Category: Supernatural
Genre: Breeding, Dean already has a family, F/M, Human Dean, M/M, Merpeople, Messed Up Sex, Rock Sex, Sex, mermaid Castiel
Language: English
Status: Completed
Published: 2018-11-27
Updated: 2018-11-27
Packaged: 2019-09-01 12:39:35
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 1,096
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16765336
Author URL: https://archiveofourown.org/users/abiotic_butterfly/pseuds/abiotic_butterfly
Summary: Castiel has reached the age of sixteen, and that means for all Merpeople that it’s time for the annual breeding. This time, it’s Castiel’s turn.





	Under The Sea

The time was coming and Castiel was rushing to figure out what to do. It was the eve of his sixteenth birthday, the day he and all the other Merpeople would go up to shore in search of a prospective lover. 

He had to be ready to get there as quick as possible, it was his job to catch whoever was there that had the best qualities in a mate.

He could feel the heat creep up on him, the one that they all got at this age, and only this age. They were a rare species that only had one child each, at the age of sixteen they were put a wild and insane heat that would send their bodies into shock till they were stuffed full with cock. 

Females wouldn’t do; they were al programmed to like men. If one of them liked females they wouldn’t continue their line and would die out quickly. Even with their lifespan of a hundred years, throughout the centuries of earth it was nothing. 

Castiel’s fire inside him was starting to become too much and he would have to surface and find another male fast. He could feel his hole opening up, one that would only morph on his day. 

He whimpered pathetically as he massaged around the newly forming hole. He was going to need someone fast and someone good. 

He bit his lip as hard as he could when a tremor ran through his body and he felt himself shake. He groaned as he released. He was going to have to start swimming now if he was going to find a mate soon.

He left the cave he and his father lived in and swam all the way to the top of the ocean, peering around to see if there were males that would fit the given mateable description. 

It was a bright and sunny day so thankfully tons of people were out swimming and that’s when he spotted him. 

He was a tall and masculine man, mussels flexing when he picked up a smaller boy, a bright smile on his freckled face as he looked to a dark haired woman. Castiel could practically feel his hole gape at the sight.

He had to have this man fuck him.

The only question was how, clearly he was already with a woman, humans were so strange when it came to their mating rituals, usually preferring females. How weird.

He swam in closer, trying to hide himself as best as he could, scaring people was always something he was taught to avoid. If he got close enough he could use his pheromones to lore the man in. All he had to do was brush up against him and the blonde would be putty in his hands.

He dove under the crashing waves and slowly but carefully swam over to his legs, purposely rubbing his large blue fin against the other males leg. 

He retreated back to way he came and started to swim towards the rock that was far away from people where they wouldn’t be able to see his soon to be coupling.

He turned his head to see the man's legs stuttering, he had learned everything in breeding class about how this would work. Once he had made contact this would go straight to the human males brian and send shock waves of need and sex that only the Merpeople would be able to fix. So he would instinctual follow his brain in telling him where his needed fuck would be and he’d follow, making up whatever lie he needed to in order to accomplish the new goal his mind set; and that was to breed. 

So Castiel went through with his plan of waiting as the rock for his new mate, knowing it was only a matter of when that handsome man would come swimming around the corner and fuck him silly.

He leaped onto the rock, his body burning with desire at this point, the overly warm rock not doing anything to calm him. 

He was starting to whine and rub his scales against the jagged rock when the strong man he’d picked swam around the corner and he practically threw himself at the taller male.

He grunted but immediately latched himself onto Castiel by kissing and grinding against him, the Merman gasping at the feel of a hard cold pressed against his scales. “F-Fuck me.” He whispered, his mouth closing around the other males ear, biting at the earlobe.

His chosen mate pushed him up onto the rock and tore off his own beach shorts, his cock hard and ready to fuck. So with ease of his newly sex crazed and blown out mind he pushed his dick is die Castiel’s warm and loose hole.

The man above him let out a groan and Castiel let out a choked moan, his arms wrapping around his breeding partner. “Fuck! Oh that’s good~” He vibrated when the man started to fuck in and out of him. His self made slick that seemed to be running everywhere was now coming in handy. His hole that seemed loose enough to take this man and twenty others was now closing around the cock inside of him like a vice. 

Castiel didn’t know what he was missing out on until he felt a connect like this. “Aw~ Fuck! Ah! Hh-“ He was bouncing against the rock with Dean’s harsh trusts, his body pulsing with energy as he readied itself to take in the other mans cum. 

“Fuck! Go harder!” He grunted at the speeded up thrusts, his head falling back in pleasure as he hold spazzed and his body convolusing. He could feel a warm and sticky substance fill his body and a part of him could feel the impending loneliness ness that was to come in the following eighty four years to come. He would never take another mate, he would never get to feel like this forever.

“W-What’s your name?” He breathed out between gasps for breath he didn’t need.

“Dean…you?” The man was staring at him with the most gorgeous green eyes he’d ever saw. 

“Castiel.” His gaping mouth was covered by…Dean’s mouth and it was amazing and it was beautiful and it was everything. He pulled away and moaned as his hole slowly closed, trapping the cum inside his body. “I must go…goodbye, Dean.” He stroked the other man's cheek and leaned away from the rock to fall into the ocean and swim away, leaving the other man dazed by the rock.


End file.
